What do the numbers on binoculars mean? It’s a common question for any avid nature lover, birdwatcher, hunter, or outdoor enthusiast. If you’re an expert in all things outdoors, you probably already know all about concepts like objective lenses and binocular lenses. However, if you’re just beginning to invest in your first resources for outdoor adventures, you may need some extra help.
The numbers on binoculars aren’t just there to confuse and bewilder you. These digits help highlight things like which binoculars are best for you if you wear glasses and which ones will help you get a better view of specific landscapes and focus points.
Today, we’re going to explore the numbers on your binoculars and why they make a difference to regular or compact binoculars.
Defining the Numbers on Binoculars
Defining the numbers on your binocular lenses can be complex when you’re a beginner. You will need to define and understand various numbers before making your purchase. Here are just some of the points to look at.
Field of View and Angle of View
The field of view or angle of view is the binoculars number which refers to the amount of wide area the main objective lenses can capture. This number can sometimes be expressed as an angle or as a measurement of so many feet per metre or yards per metre.
If you intend to use your binoculars to cover more area, rather than looking at distant objects, you’ll need to buy binoculars with lower magnification and a higher viewing area. If you have an angle of view, you’ll need to multiply it by 52.5 to get your field of view. For example, if you have a 7.2-degree angle of view and multiply that by 52.5, you’ll get 378 feet for a field of view.
The number is most often measured using linear feet or at a distance of 1000 yards in angular degrees. A larger field of view has many advantages, including the ability to see a broader range of creatures in a denser background or track faster-moving objects through your lens.
Magnification Power
Magnification, along with the field of view, is one of the top binocular measurements considered by buyers.
People often assume that higher magnification on their binoculars is always a good thing. However, when you understand binocular numbers fully, you’ll learn that magnification isn’t everything. The magnification of your binoculars will sometimes be listed as aperture or lens size. This is a combination of two numbers with a multiplication operator.
For instance, an example of binoculars’ magnification might be 9 x 40. This means any binocular with this number can easily magnify an object by nine times their actual distance. Higher magnification in a pair of binoculars may cause instability and lack of clarity.
If you have a lot of light in your chosen destination and you’ve got a stand to hold your binoculars in place, there shouldn’t be as much trouble with your magnification.
When making your binocular purchasing decision, don’t forget to consider all the other factors, from the field of view, to whether your lenses are fully coated.
Which Magnification Is Best for Binoculars?
The exact degree of magnification you need for your binoculars will depend on several factors. Remember, the first number indicates the strength of the magnification, while the second number refers to the objective lens size, which is measured in millimetres.
The main purpose of binoculars is to allow you to see objects at a distance with more detail and clarity than you could with the naked eye. When choosing your binoculars, you may ask:
Which Is Better, 12×50 or 10×42 Binoculars?
This can be a complicated question to answer as it depends on the kind of viewing you’re going to be doing. The objective lens in the 12 x 50 binoculars will be larger, making them heavier to carry around if you’re on the move. However, you will get a greater level of magnification too. Both of these binoculars are likely to offer a similar level of clarity, though the 12 x 50 may be better for lower light conditions.
Which Is Better, 10×50 or 20×50 Binoculars?
With a set of 10×50 and 20×50 binoculars, you’re getting the same objective lens size across both devices. The only difference is in the magnification ability of each set. Different manufacturers will offer slightly different experiences in this field of view. When buying binoculars with 20 times zoom, it’s worth remembering the higher magnification number will make it harder to maintain clarity. Before deciding, you may need to check the binoculars’ strength in a store.
What Is Better, 8×42 or 10×42 Binoculars?
Both of these kinds of binoculars will give you the same objective lens size. However, the 10 x 42 binoculars should help you to zoom in closer to the thing you want to see. It might be worth having binoculars zoom explained by the company you’re buying from, so you can get an insight into the steps you’ll need to take to maintain a clear image with each set of binoculars.
Eye Relief Number
Outside of the magnification numbers and size of your lenses, you may also need to check the eye relief number on your binoculars. This number will be important for eyeglass wearers as it represents how far you can keep your eye away from a particular pair of binoculars while using them.
When discovering what binoculars’ numbers mean, don’t underestimate the power of binocular eye relief.
Some manufacturers use multi-coated lenses or multiple layers on their lenses which means you have to get really close to see the full image correctly. You may need to look at single layer lenses if you have thicker glasses. If your eye relief number doesn’t match your glasses, you won’t see your image correctly.
Regular eye relief numbers vary from 9 to 13mm, while long-term eye relief numbers are more likely to be above 14mm. Eyecups can also be folded down for people who wear glasses to see their objects more easily and get close to the lens.
Exit Pupil Numbers and Close Focus
Exit pupil numbers are another important consideration when determining which set of binoculars to buy. For example, numbers make it possible to view objects even when in low light conditions. If you want a close focus on various images within low light conditions, you’ll need a bigger exit pupil size.
Many binoculars will tell you the exit pupil size directly. However, you can also measure your ability to see in low light conditions by holding your binoculars around eight inches away from your eyes. You should see two dots in the middle if you have enough light. That dot is where the light hits the lenses and enters your eye so that you can see things at a distance.
The “close focus” number is the number that indicates how close you can get to focus on any specific object. For instance, if you’ve got a close focus of eight feet, you could focus on any object up to eight feet away and use your binoculars to bring the image closer to you.
Meaning of Numbers on Binoculars
What do the numbers on binoculars mean? The numbers on your binoculars are crucial, from objective lens diameter (or objective lens size) to exit pupil numbers that combine with your objective lenses to determine how much light you need to see images correctly. Knowing exactly what you’re going to be using your binoculars for is crucial.
Considering your needs will help you determine whether you’re going to have more light-gathering around you during your binocular use or whether you need a low light performance. You’ll also need to think about how much magnification you’re going to need. Remember, larger objective lenses and more light with your lens diameter will allow you to achieve better views with the same magnification.
If you’re confused about your binocular’s light-gathering ability, the size of the ocular lens, or how well your larger lenses will perform in bright light, it’s best to speak to an expert. Most binoculars come with specific product descriptions, so you can better choose quality binoculars for different needs.
Remember, try not to get too caught up on magnification or field of view when choosing between popular models. The way light can enter your lens or how your binoculars feel when using your eyeglasses can also make a huge difference to your viewing experience.
Additional Resources
Sam loves to learn about animals and their habitats. He has been a nature lover from a very young age, and has been writing papers and articles about wildlife for as long as he can remember.